R looking for the wrong java version
java, r, windows
Solution
You problem depends on 64/32 bit versions. You run 32-bit R, which use 32-bit command prompt and find 32-bit java. If you use 64-bit R then it runs 64-bit command promt and proper java.
You could check it by run 32-bit command promt (following this post):
- Click Start.
- Type `%windir%\SysWoW64\cmd.exe` in Start Search box.
- Press Enter.
- Type `java -version`
In my system it fails because I don't have 32-bit java. With standard cmd.exe I get proper path.
For possible solution there are two ways. Install 32-bit R and 32-bit Java or 64-bit R (which is officially supported from 2.11 version) and 64-bit Java. On my system (64-bit Windows 7) I've got both sets, so on 32-bit combination I get:
> system("java -version")
java version "1.6.0_20"
Java(TM) SE Runtime Environment (build 1.6.0_20-b02)
Java HotSpot(TM) Client VM (build 16.3-b01, mixed mode, sharing)
And on 64-bit:
> system("java -version")
java version "1.6.0_18"
Java(TM) SE Runtime Environment (build 1.6.0_18-b07)
Java HotSpot(TM) 64-Bit Server VM (build 16.0-b13, mixed mode)
On 64-bit version you could call 32-bit Java using 32-bit cmd:
shell(
"java -version",
shell = file.path(Sys.getenv("windir"),"SysWoW64/cmd.exe")
)
java version "1.6.0_20"
Java(TM) SE Runtime Environment (build 1.6.0_20-b02)
Java HotSpot(TM) Client VM (build 16.3-b01, mixed mode, sharing)
About Shane's comment I think the question is how R get path to 32-bit cmd. Because I can't find a way to call 64-bit cmd on 32-bit R.
Problem
I installed/uninstalled java jre/jdk now many times and finally installed the older version 1.6.0_17 which is now located at "C:\Program Files\Java\jre6\bin". Now after all if I call 'java -version' within R i can see that R is looking for Java at the old path which is now wrong. The question is: Why is R looking for Java at the wrong path even so the windows path is set correctly? There are no double entrys within the windows path as far as I can see and I restarted R as well as Windows more then once since then. Any Ideas where R takes the wrong path from? On windows shell: ``` > set [..] OS=Windows_NT Path=C:\Program Files\Java\jre6\bin; [..] > java -version java version "1.6.0_17" Java(TM) SE Runtime Environment (build 1.6.0_17-b04) Java HotSpot(TM) 64-Bit Server VM (build 14.3-b01, mixed mode) ``` within R: ``` > system("java -version") Error: could not open `C:\Program Files (x86)\Java\jre6\lib\i386\jvm.cfg' ```